Recently, there are a lot of post here about fellow steemians who have lost their steem or other crypto currencies. During a hardfork, there is a big possibility that a single blockchain can spilt into 2 as the miners or the witness nodes may not have updated or agreed on to the new upgrades. The result is that there may be 2 chains at one time and this will present a lot of problems especially if they were to remerge. Many coins can be lost during this period if you happen to be on the wrong block which has been orphaned.
A lot of times, wallet maintenance by an exchange will also cause the same problem. During wallet maintenance, transfers may get orphaned and thus it is best to avoid sending coins in and out during a hardfork or wallet maintenance from exchanges.
Currently, big exchanges like Polinex are growing too fast for their support staff to cope with the number of issues. The first thing to do is to contact support and raise a ticket and provide as much information as possible such as transaction hashes, wallet address etc. If they do not respond after 2 hours, you can escalate the case. Don't try to raise too many tickets for the same problem, it will only slow things down further. I had issues before, most take a day or 2 to resolve but currently, it may sometimes take much longer due to the high volume and staff shortage.
So before any transfer to and from exchanges, it is best to check if there is any wallet maintenance or if there are any hard or even soft forks happening around that time for the specific coin you intend to transfer.
Any usual, stay Safe.
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